I have it currently set up a simple set up as follows on my Model B RasPi.

Attached is:

1 16 GB Class 10 Transcend SD Card.

1 8 GB USB drive.

1 16 GB USB drive.

Network cable connected to my Router.

Power supply (Of course)

More powerful power supply will allow you to connect USB HDDs without additional power supply. For ex. if you connect a Samsung Phone Charger with 700 mA, you won't be able to connect external HDD without additional power supply.

I connected LG Charger that came with my Nexus 4, which produces 1.2 A output, seems to make my 1 TB WD external HDD work with the Pi.

Software Setup:

Raspbian OS (Previously I tried Arch, but I found raspbian nicer.)

LVM (Logical Volume Management)

Transmission BT

youtube-dl

Initial Configuration:

Installed Rasbian OS on my Pi. To know how to do that go here:

http://elinux.org/RPi_Easy_SD_Card_Setup

By default, Raspberry Pi allows SSH access with the default username pi and password raspberry. I accessed it directly from the network.

Configure root password

sudo passwd root

command will allow you to change your root user password so that you can login using root account.I always use root account and have never logged in using pi account.

Be careful. Logging in using root and performing incorrect operations may cause unstable OS or crash.

Configure Static IP address

To configure static IP address I simply edited my /etc/network/interfaces file that now looks like this:

Re-connected to my raspberry pi using new static IP address.Update the pi

apt-get update && apt-get -y upgrade

Its always good to have this run first time, before you do anything.The LVM setupOK. The idea behind configuring LVM on my pi was nothing but to combine all the space available on different partitions to form a single logical volume and mount it at a single point, so that I can keep huge stuff inside single mount point.Here's how my fdisk -l looks like:Note: Removed information that is not required as of now.

OK. So there's three devices.First memory card that RasPi boots from, Second the 8 GB USB and third 16 GB USB drives. /dev/mmcblk0, /dev/sda and /dev/sdb respectively.There's two partitions on /dev/mmcblk0p1 and /dev/mmcblk0p2 used for RasPi itself. The third one was created by me. Note that the type of partition is Linux LVM. Similar partitions created on USB drive but only one on each that lie on full drive.To know how to create a partition on a disk go here:

vgcreate will combine space from /dev/mmcblk0p3 /dev/sda1 /dev/sda2 to create a single Volume group.lvcreate will create a logical drive out of that volume group.mkfs.ext4 will create an ext4 filesystem on the logical volume.We need to mount this new logical volume.

# mkdir /data
# mount /dev/datavg/lvol0 /data
# chmod 777 /data

So our new filesystem which comprises space from three devices, will be accessible on /data partition.Now, we need this logical volume to be mounted across each reboot. To make it happen, ran following command.